This specification relates to models for machine learning.
Example machine learning models include neural networks. Neural networks employ one or more layers of nonlinear units to predict an output for a received input. Some neural networks include one or more hidden layers in addition to an output layer. The output of each hidden layer is used as input to the next layer in the network, i.e., the next hidden layer or the output layer. Each layer of the network generates an output from a received input in accordance with current values of a respective set of parameters. Neural networks may be trained on machine learning tasks using training data to determine trained values of the layer parameters and may be used to perform machine learning tasks on neural network inputs.